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    <script>
        // 今天是星期二 计算n天后是星期几
        var weekday, plusDay, intDay;
        plusDay = 1000 % 7;
        // alert(plusDay);
        switch(plusDay) {
            case 1: alert("1000天后是星期三");break;
            case 2: alert("1000天后是星期四");break;
            case 3: alert("1000天后是星期五");break;
            case 4: alert("1000天后是星期六");break;
            case 5: alert("1000天后是星期日");break;
            case 6: alert("1000天后是星期一");break;
        }
        intDay = parseInt(prompt("请输入天数", ));
        plusDay = intDay % 7;
        switch(plusDay) {
            case 1: alert(intDay + "天后是星期三");break;
            case 2: alert(intDay + "天后是星期四");break;
            case 3: alert(intDay + "天后是星期五");break;
            case 4: alert(intDay + "天后是星期六");break;
            case 5: alert(intDay + "天后是星期日");break;
            case 6: alert(intDay + "天后是星期一");break;
        }
        


    </script>
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